Satellites are often used to communicate between different points on the earth. The coverage of a satellite refers to the amount of the earth's surface that can communicate with the satellite. Since the satellites must orbit the earth, different parts of the earth may communicate with the earth at different times.
One of the most common satellite systems is a geosynchronous satellite. Those satellites orbit at the same rate as the earth so that each satellite always communicates with the same part of the earth. There are many limitations of geosynchronous satellites, however. One such limitation is their great height. Because of their great height, the communication delay back and forth to the satellite can become noticeable. Also, the cost to boost a satellite into this very high orbit can be very high. Finally, only so many slots are available in the geosynchronous orbital plane. Many of those slots are already taken.
Previous patents by the assignee of the present invention have been directed to the advantages of elliptical satellites. These advantages include lower earth orbit and hence less delay, easier payload and hence less cost to boost into orbit. An additional advantage includes asymmetric coverage of the earth.
This asymmetric coverage can tailor certain parameters to population and or time of day.